Raisin treatment method and apparatus



March 3, 1936. T w w FQRREST 2,032,406

RAISIN TREATMENT METHOD AND APPARATUS I Filed June 23, 1933 2 Sheets-Sheet 1 Far/6am 6 6 PlE 2 8 v INVENTOR 1 7770/7105 14 h/f5/v-e52 March 3,1936, w w FORREST 2,032,406

- RAISIN TREATMENT METHOD AND APPARATUS Filed June 25, 1933 2 Sheets-Sheet 2 Z/ .35 I i INVENTOR 7/70/7105 14 M f'arres/ /3 /7 ATTORNEYS.

Patented Mar. 3, 1936 RAISIN TREATMENT METHOD AND APPARATUS Thomas W. W. Forrest, Fresno, Calif., assignor to Sun-Maid Raisin corporation Growers of California, a

Application June 23, 1933, Serial No. 677,267

4 Claims.

This invention relates generally to methods and apparatus for treatment of raisins, and is adapted particularly for use by the dried fruit industry where raisins are processed to place the same in marketable condition. The present application is a continuation in part of subject matter disclosed in copending application Serial No. 582,718 filed December 23, 1931.

The processing of raisins commonly includes a cap-stemming operation, which serves to remove the stems from the raisins by a mechanical action. In the past this cap-stemming operation has given considerable difiiculty. The capacity of the cap-stemming machines has been. definitel-y limited, mutilation of the skin of the raisins with resultant extrusion of juice is common, and the machines must be frequently shut down for cleaning and repair.

It is an object of the present invention to provide a raisin treatment method and apparatus companying drawings.

Referring to the drawings:

Figure l is a diagrammatic view illustrating the method of the present invention in the processing of raisins.

Fig. 2 is a diagrammatic view showing the manner in which my method can be applied to conventional cap-stemming apparatus.

Fig. 3 is an end view partly in cross section showing my preferred cap-stemming apparatus.

Fig. 4 is a cross shown in Fig. 3.

sectional detail showing the construction of certain parts of the machine Fig. 5 is a side elevational' view of the machine shown in Figs. 3 and 4.

Referring first to Figs. 3, 4 and 5, the cap-stemmer illustrated consists of a main frame H), which serves to support an inner sub-frame ll. Carried within the sub-frame H, there is a stationary conical shaped part I2, and conical shaped part !3.

a rotatable Part i2 is foraminous,

in that it is formed of relatively thin sheet metal provided with inclined slots M. The upper end of the stationary part l2 projects thru an opening provided in a platform It, this platform being removably supported by the main frame Ill. The lower end of the part It is held in proper axial alinement by ring H, which is carried by 5 the sub-frame ll. Likewise the lower portion of this part I2 is preferably corrugated, as indicated at IE, to secure more effective action upon the raisins as will be presently explained.

Theinner rotatable part l3 of the cap-stemmer consists of a body l9 provided with a conical shaped peripheral surface, and mounted axially upon a rotatable vertical shaft 2!. Fixed to and covering the outer conical periphery of body [9, there is a surfacing of metal screening 22. Note that the screening 22 is spaced with respect to the inner surface of the outer conical shaped part I2, to afford a space for passage of the raisins being treated.

As will be presently explained, it is desirable to permit vertical adjusting movement of the inner rotatable part is of the cap-stemmer. Such vertical movements are made possible by a spe cial form of bearing for shaft 2!. Thus within the body is of the rotatable part it, shaft 2| is provided with a journal 23, in which shaft 21 can be vertically adjusted. Journal 23 is suitably supported by the main frame ls. The lower portion of shaft 2i is also journaled within a suitable thrust bearing block 24 which is vertically adjustable within a guide 26. Guide 26 is likewise secured to the main frame l0. Extending horizontally upon the opposite sides of the thrust block 2d are the levers 21, corresponding ends of which are secured to the frame l0 by links 25. The other corresponding ends of levers 21 are connected to a common cross-head which is provided with a nut threaded upon a screw 28. Screw 28 is mounted upon frame IE] and can be turned to any desired adjusted position by the hand wheel 29. Pin and slot connection 3! connects the intermediate portions of levers 21 with the bearing block 2 By turning hand wheel 29 thrust bearing block 24 and thus shaft 2| can be adjusted vertically within certain limits. 4.5

As representative of suitable means for driving shaft 2! at a relatively high rate of speed, as for example about 1200 R. P. M., there is shown an electric motor 32, mounted upon frame ill and provided with a drive pulley 33. Pulley 33 is connected to a pulley 23 i fixed to shaft 24 by a belt drive 36.

In order to tend to retard the downward rate of flow of raisins to the cap-steminer, I preferably cause a draft of air to flow upwardly between I side of frame the outer and inner parts I2 and I3. This can be accomplished by enclosing the sides of subframe II with walls 31. A stream of air is introduced into this enclosure, as by means of conduit 38. This air flows thru the slots in part I2 and is delivered upwardly thru platform I6. Such an air draft not only retards the rate of the raisins to the cap-stemmer, but may also tend to aid in effecting cooling of the raisins, in the event the raisins have been heated in a prior step of the processing.

Immediately below the conical part I 2, a horizontal screen 39 is provided for receiving the raisins, this screen being supported by a suitable frame 4I. Frame 4| is supported by resilient members 42 and is adapted to be vibrated by suitable means, such as an an excentrio rod 43 and excentric 44. Excentric 44 is shown driven by an electric motor 46, thru the belt drive 41. Screen 39 is of such a mesh that it will pass the stems, and is so arranged that when vibrated the raisins are continuously moved toward one It where they are discharged.

In addition to the parts of the cap-stemmer described above, I provide means for introducing a spray of oil into the space between the parts I2 and I3. Thus as shown in Fig. 4 the conical shaped body I9 is recessed to accommodate longitudinal tubes 5|, which are provided with apertures 52 for the discharge of oil thru screening 22. At their upper ends, tubes 5| are connected to a passage representative of suitable means for introducing a controlled quantity of oil in passageway 53 there is shown a reservoir 54 mounted upon a suitable support, and the pipe 56 leading from the lower portion of this reservoir discharges into the passageway 53. The rate of flow of oil can be controlled by valve 51. Oil introduced from reservoir 54 is discharged by centrifugal force thru apertures 52 and by virtue of its velocity and also by virtue of the fact screen 22, a finely atomized mist or spray is provided for effectively securing the results to be presently described.

Operation of the machine described above, and the carrying out of certain phases of the present method, is as follows:As the raisins to be treated flow into the machine from hopper 58 they are caught up and swirled about in the space between the stationary conical part I2, and the rotary screen 22. Repeated impact of the raisins upon the inner surface of the stationary part I2, and the surface of the rotary screen 21, which is accompanied by rolling or turning movement of the raisins, causes the stems of the raisins to be removed. The raisins, together with the removed stems, gradually progress downwardly until they are received upon the shaker screen 39. A final abrasion is eifected by the lower corrugated portion of part I2, which tends to reduce the veloc-- ity of the raisins. The removed stems including those discharged thru slots I4, pass thru screen 39, while the stemmed raisins are delivered from the end of the screen. The vertical position of the rotary part I3 should of course be adjusted to secure proper cap-stemming of the particular character of raisins being handled.

While the raisins are passing down thru the space between the inner rotating screen 22, and the outer stationary part I2, this space also continues to receive a small quantity of atomized oil, being discharged from the apertures 52. The continual supply of this oil has a marked effect upon operation of the machine, and upon the cap- 53 formed axially of shaft 2|. As

that the oil must pass thru capacity, compared to the speed of operation and 7 capacity which would be permissible without such introduction of oil. At the same time, and even at the greatly increased capacity, it has been found that the skins of the raisins are not mutilated, although the stems are still effectively removed. Furthermore, the machine, by virtue of the use of oil in the manner described, is made substantially self-cleaning. This is due not only to the fact that mutilation of the skins of the raisins is minimized, but also to the fact that the stems or other material removed from the raisins during the cap-stemming operation would not tend to adhere to the surfaces provided with an oil film, to clog the inclined slots I4.

The non-clogging feature of my cap-stemmer is also due in part to the use of a relatively thin metal for the part I2, in place of a wire screen, and to the fact that the slots I4 in this thin sheet metal are inclined in the direction of rotation of the inner part I3. However, the use of relatively thin metal would not be practical if it were not for the fact that the use of oil in the manner described minimized wear upon this part.

thus making possible a long useful life without frequent repairs.

In Fig. 1, I have shown the several steps of a complete processing method incorporating the cap-stemmer described above, together with the heater shown and claimed in the aforesaid application Ser. No. 582,718. In this method the raising are first passed thru a heater I, where they are subjected for a short time to a relatively high temperature. Following removal from this heater the raisins are cooled and then introduced into the cap-stemmer 2. From the cap-stemmer 2 the raisins are treated in a steamer 3, from which they are delivered to the seeder 4. The seeded raisins can then be contacted with a suitable coating solution as indicated at 5, to produce the final marketable product. In this Fig. I, cap-stemmer 2 is intended to represent a capstemmer substantially in accordance with that previously described with reference to Figs. 3 to 5 inclusive. The amount of oil introduced into this cap-stemmer should preferably be maintained at a minimum, to secure the desired results. While it has been found that a relatively small amount of oil is required to secure the desired results, a certain amount of this oil will remain upon the raisins received by the steamer 3. However during the steaming process traces of this oil which may remain from the cap-stemming operation are effectively removed, so that no oil of this character appears upon the final product. This is desirable because the oil introduced into the capstemmer is usually a mineral oil, such as white oil, and material of this character upon the final product is objectionable.

While we have found it desirable to introduce oil directly into the cap-stemmer, it is also possible to secure good results by contacting the raisins with a small amount of oil, before the raisins are delivered to a conventional mechanical cap-stemmer. Thus as shown diagrammatically in Fig. 2, the raisins are shown being introduced into a tumbler 6, where they are subjected to a spray of oil. From this tumbler the raisins are delivered to the mechanical cap-stemmer 1. The oil thus carried into the mechanical cap-stemmer will serve to maintain a thin film of oil upon the surfaces with which the raisins are contacted to effect cap-stemming. Therefore this cap-stemmer can likewise be operated at a relatively high capacity, with a minimum amount of mutilation to the skin, and with a greatly reduced tendency towards clogging. From the cap-stemmer I, the raisins are shown being delivered to the processing steps 8, to form the final product.

I claim:

1. In a method of treating raisins, the steps of subjecting the raisins to repeated impact between relatively moving surfaces, thereby removing stems from the same, maintaining a film of oil upon said surfaces, and subsequently removing any oil adhering to the raisins by steaming.

2. In apparatus of the character described for cap-stemming raisins, a conical part having a roughened outer peripheral surface, a rotatable shaft upon which said shaft is axially mounted, an outer conical shaped member surrounding said first named member and likewise having a roughened inner peripheral surface, said peripheral surface of said members spaced apart in a radial direction, means for passing raisins downwardly between said members, and means for centrifugally spraying oil from the inner rotatable part into the space between said parts.

3. In apparatus of the character described for cap-stemming raisins, inner and outer nested parts, the inner part including a conical shaped screen, means for effecting rotation of the inner part about its axis, the outer part being like:- wise conical shaped and having thin sheet metal walls spaced radially with respect to the outer periphery of the inner part, and means for causing raisins to pass downwardly between said parts to effect mechanical removal of the stems therefrom, the sheet metal walls of the outer part having slots, substantially all of said slots being inclined at a substantial angle with respect to the axis of the inner part.

4. In a method of treating raisins, the steps of subjecting the raisins to repeated impact between relatively moving surfaces to effect removal of stems therefrom, and maintaining a film of oil upon said surfaces.

THOMAS W. W. FORREST. 

